The present invention relates to an ink jet system printer and, more particularly, to an ink issuance control system in an ink jet system printer of the charge amplitude controlling type.
Generally, in an ink jet system printer of the charge amplitude controlling type, ink droplets are continuously emitted from a nozzle without regard to whether or not the actual printing operation is performed or not performed while the ink jet system printer is supplied with power. The ink droplets not contributive to the actual printing operation are directed toward a beam gutter for recirculation purposes. A portion of the volatile component included within the ink liquid is unavoidably decreased due to volatilizing while the ink droplets travel in the air from the nozzle to the beam gutter.
Accordingly, the concentration of the ink liquid is gradually increased when the ink droplets are continuously emitted from the nozzle without performing the actual printing operation. The ink liquid concentration must be maintained at a predetermined value to secure the ink droplet formation or to ensure stable printing in an ink jet system printer of the charge amplitude controlling type. Moreover, there is a possibility that the ink liquid compositions are oxidized while the ink droplets travel in the air from the nozzle to the beam gutter. The oxidized compositions will deteriorate the ink liquid and influence the stable operation of the ink jet system printer.